1. Field of the Invention
The present invention relates to a valve seal member and valve.
2. Statement of the Problem
A valve comprises a valve body containing a valve mechanism. Inlet and outlet ports communicate between the valve mechanism and the outside world. The body often comprises portions that are assembled to form a valve chamber including one or more valve seats and two or more passages, such as inlet and outlet ports. The valve mechanism can move in the valve body and can selectively contact and unblock the one or more valve seats in order to perform the valve function, thereby selecting and de-selecting ports.
FIG. 1 shows a portion of a prior art valve 1. The prior art valve 1 includes a valve body 2 and a valve seat insert 3. The prior art valve seat insert 3 can include a valve seat 4 that is contacted by a valve poppet or other valve mechanism. The valve seat insert 3 is assembled to a corresponding cavity of the prior art valve body 2 as part of forming the prior art valve 1. A prior art port insert 5 is further assembled to the valve body 2, with the prior art port insert 5 matching up with the valve body 2, as shown, to form two or more ports, such as the ports 102a-102c shown in the figure. The ports can comprise inlet ports, outlet ports, or both. The prior art port insert 5 contacts the prior art valve body 2 at multiple sealing regions 8. At the sealing region 8, the prior art port insert 5 seals to the valve body 2 by compression and deformation. The prior art port insert 5 is commonly a seal formed from an elastomeric material, such as rubber.
The prior art valve seat insert 3 can be sealed to the prior art valve body 2 by a weld region 7. The weld region 7 can be formed through ultrasonic welding, allowing the weld region 7 to be a distance from the outside of the valve.
The valve seat insert 3 further includes a ring seal 6 that seals an inner portion of the valve seat insert 3 to the valve body 2. The ring seal 6 is received in a channel 9 formed in the valve seat insert 3. The prior art ring seal 6 can comprise an O-ring or similar sealing device.
Consequently, the assembly of the prior art valve seat insert 3 into the prior art valve body 2 involves three separate sealing regions, adding complexity to the manufacturing process. The three separate regions are the ring seal 6, the weld region 7, and the sealing region 8. In addition, where port 102b is an inlet port, there may continuously be pressurized fluid in the port 102b. Therefore, there can be an increased likelihood of seal failure at one or both of a sealing region 8′ and the ring seal 6.